Incontinence is the involuntary loss of urine. There are several different types based on the pattern of urine leakage and the structure and function of the bladder and the urethra (the tube through which urine exits the body).

Bulking agents are an effective incontinence treatment primarily for stress incontinence, in which pressure on the bladder from a sneeze or cough can force urine to leak. The technique is of particular benefit to women who suffer from intrinsic urethral sphincter dysfunction (ISD) in which the urethral sphincter cannot close completely.

The technique uses collagen or other FDA-approved synthetic materials to provide additional support. “They tighten the position of the urethra, where there isn’t enough strength to control it,” says Jean Fourcroy, MD, a Washington D.C. urologist, a consultant to Walter Reed Army Hospital, and former Food and Drug Administration medical examiner.

However, you need to make sure that you actually have stress incontinence before you proceed with injection of a bulking agent. “If you haven’t identified that this is purely stress [incontinence], it might not be beneficial,” Dr. Fourcroy warns.

Bulking Agent Incontinence Treatment: How the Procedure Is Performed

The incontinence treatment begins with a small scope placed into the urethra; once the scope is positioned properly, a needle is passed through it. Your surgeon will guide the needle very near to where the urethra meets the opening of the bladder, and inject the bulking agent at that location. Once injected, the agent will solidify and press the urethral lining inward, causing the urethra to close off. This partial blockage will help the urethra remain closed during a cough or sneeze, or when exercising or lifting heavy objects.

There are a number of FDA-approved bulking agents available for this incontinence treatment, including:

Cross-linked collagen (Contigen).

Carbon-coated beads (Durasphere).

Ethylene vinyl alcohol copolymer implants (Uryx, Tegress).

Particles of calcium hydroxylapatite in a gel carrier (Coaptite).

Polydimethylsiloxane (silicone, Macroplastique).

For a few days following the procedure, you might experience irritation when you urinate. Some patients will have to use a catheter (a tube placed into the urethra to allow urination) until swelling around the urethra goes down. Bladder infections also are a rare side effect.

Bulking Agent Incontinence Treatment: Pros

The treatment is simple and non-invasive. It can be performed in a doctor’s office or as an outpatient procedure in a hospital. It can be done under local or general anesthesia and takes about half an hour.

The procedure is effective. “All of [the bulking agents] appear equally efficacious, curing a quarter of patients and improving another 50 percent of patients,” says Craig Comiter, MD, associate professor of urology at Stanford University Medical Center and a spokesman for the American Urological Association.

Bulking Agent Incontinence Treatment: Cons

This incontinence treatment is not for everyone, however.

It's less effective for men. Bulking agents do not treat male stress incontinence very well, especially incontinence due to a removed prostate gland. Men have had better results using an inflatable artificial urinary sphincter (AUS) that puts pressure on the urethra.

Allergies can occur. Doctors will need to make sure you’re not allergic to the bulking agent. About 2 percent of patients are allergic to collagen, for example. You might need to undergo a skin test prior to the injection with a bulking agent.

Repeat procedures may be necessary. If you use collagen as a bulking agent, you might have to go through the procedure every couple of years. That’s because collagen breaks down and is absorbed by the body over time.